Generally speaking, the present invention relates to an improvement in a timing mechanism wherein at least two separate cam means are carried by a shaft, and wherein a motor drive means causes rotation of the cam means, the improvement being characterized by a first cam means fixedly connected to the shaft, second cam means freely rotatable about the shaft, and coupling means coupling the motor drive means to the shaft and the second cam means, the coupling means adapted to permit the first and second cam means to be simultaneously rotated at different speeds.
This invention relates, in general, to a timing mechanism and in particular to a timing mechanism particularly adaptable for controling a laundry dryer through a timed fabric treatment cycle.
Some automatic clothes dryers include an anti-wrinkle control system that provides for rearranging and refluffing permanent press fabrics every few minutes if they are not removed from the dryer at the end of the automatic or timed drying period. More specifically, at the end of a permanent press cycle, a buzzer sounds to remind a housewife, for example, that her clothes are ready. If she is busy or out of the home, the anti-wrinkle control starts the dryer at predetermined intervals, for example every five minutes and tumbles the clothes for a predetermined interval, for example, 10 seconds. At the end of each 10 seconds of tumbling, the dryer again buzzes to remind the housewife to remove the clothes. The dryer continues to "nag" in this manner for a predetermined period of time, for example, up to two and one half hours. However, for the times illustrated, total running time for the dryer would only be five minutes.
One system providing an anti-wrinkle portion of a drying cycle employed two timer motors. One motor drove the timer cams which sequentially operated the dryer at a constant speed, while a second "pulser" motor drove a cam to intermittently complete a circuit to the timer motor to advance the timer cams intermittently and to complete a circuit and intermittently cycle the main dryer motor operating the dryer and to run out the timer motor until a predetermined accumulative minutes of timer "on time" has expired a "two motor" timer useful for such a system as described in U.S. Pat. No. 3,732,383 issued May 8, 1973. Because of the decreasing amount of available space required in automatic clothes dryer operation and because of the increased amount of cost of the additional motor, it has become highly desirable to replace this conventional method of operation with a system utilizing only the single timer motor.